Supercapacitors
(SCs) are highly promising electrochemical energy
conversion and storage devices. SCs display an outstanding power performance,
excellent reversibility, long-term stability, simple operation, and
high feasibility for integration into electronic devices, including
consumer electronics, memory backup systems, and industrial power
and energy management systems. The electrode materials determine the
cell capacitance, operating voltage, power density, energy density,
and time constant of SCs. Transition metal-based electrode materials
(TMEMs) are among the most promising electrodes for SCs, due to their
outstanding energy density, specific capacitance, and quick charging/discharging
rates, in addition to their ease of preparation in a high yield from
low-cost and earth-abundant resources. Binary transition metal sulfides
(BTMSs) possess various advantages relative to other TMEMs, including
higher storage capacity, higher electrical conductivity, excellent
redox properties, better specific capacitance, quicker electron/ion
diffusion, and superior reversibility with long cycle life. Herein,
the inventory and the recent progress in the rational design of BTMS
electrodes for SCs are deliberated, spaning from the preparation methods
to the operative conditions, performance, and mechanism. To help assist
in the further development of BTMS electrodes for efficient and durable
SCs, current underlying challenges and possible solutions are identified
and addressed, with emphasis on device performance vs BTMS type and
relative merits.
